Power control winch

ABSTRACT

A winch having an integral control system wherein the clutch and brake mechanism are hydraulically actuated and the hydraulic actuating system is positioned in the winch housing. The system includes the oil supply, the control valve, the hydraulic pump and an accumulator. The pump is self-compensating and is mounted to be continually actuated by a shaft in the drive train to the winch drum. To reduce the volume of hydraulic fluid normally required in a hydraulic system and to improve the reliability, the valve is a unique no-leak type with the inlet through a bore in the valve spool and an outlet located along only one side of the spool and the valve is used in conjunction with an accumulator which allows release of the brake after shut down of the drive train. The brake mechanism comprises multi-wrap brake bands which are spring-actuated and hydraulically released, the multi-wrap enables relatively high braking force produced by a minimal spring actuating force.

United States Patent Murray et al.

1451 Sept. 4, 1973 1 POWER CONTROL WINCI-I [75] Inventors: John B. W. Murray, Whiterock;

Sommerville G. Christison, Delta; William Bonar, Vancouver, BC, all of Canada [73] Assignee: Gearmatic Co., Ltd., Surrey, British Columbia, Canada [22] Filed: 7 Oct. 5, 1970 [21] Appl. No.: 77,977

[52] US. Cl 254/187 R, 188/77, 254/150 FH [51] Int. Cl 366d 1/00 [58] Field of Search 254/187, 150 FH; 60/52 HE; 417/214, 223; 188/77 R [56] References Cited 7 UNITED STATES PATENTS 2,667,240 l/l954 Wilkinson et a1. 188/77 R X 2,958,341 11/1960 Grob 188/77 R X 2,984,985 5/1961 MacMillen 60/52 HE 3,157,221 ll/l964 Keil 417/214 2,289,387 7/1942 Stephens 254/150 FH 3,042,375 7/1962 Fahey et a1. 254/187 X 3,529,702 9/1970 Eckstein 254/187 X 3,539,046 ll/l970 Berg 254/187 X France 254/187 7 1950' Australia 254/187 9/1967 Great Britain ..2s4 1s7 [57] ABSTRACT A winch having an integral control system wherein the clutch and brake mechanism are hydraulically actuated and the hydraulic actuating system is positioned in the winch housing. The system includes the oil supply, the control valve, the hydraulic pump and an accumulator. The pump is self-compensating and is mounted to be continually actuated by a shaft in the drive train to the winch drum. To reduce the volume of hydraulic fluid normally required in a hydraulic system and to improve the reliability, the valve is a unique no-leak type with the inlet through a bore in the valve spool and an outlet located along only one side of the spool and the valve is used in conjunction with an accumulator which allows release of the brake after shut down of the drive train. The brake mechanism comprises multi-wrap brake bands which are spring-actuated and hydraulically released, the multi-wrap enables relatively high braking force produced by a minimal spring actuating force.

7 Claims, 7- Drawing Figures i 'LJ PATENTEBSEP 4 ma 3; 756; 564 v 7 sum 1 or 4 INVENTORS FlI G=ll WILLIAM SONAR SOMMEBVILLE G. CHRISTISON A fi z ATTORNEYS JOHN a. w. MURRAY PATENTEI] SE? 4 I975 SHEET204 w 7 w 1 m w I I Z E F/I4 INVENTORS JOHN B.W. MURRAY WILLIAM BONAR SOMMERVILLE G. CHRISTISON BY Q/ew! gag @15 N QFMN ATTORNEYS PATENTEBSEP 4m: 3356564 INVE ORS JO awm RAY 4 WI AM BONAR FIG: 4 22 SOMMERVILLE e. OHRI TISON BY z pa glw 4 ATTORNEYS PAIENTEBsEP 4mm 37156564 SHEU t 0F 4 may A ii i4 I Illa.Q H

INVENTORS 202 JOHN aw. MURRAY WILLIAM BONAR lFlfG==7 SOMMERVILLE G.CHRISTISON ATTORNEYS BACKGROUND OF THE INVENTION In the hydraulically controlled prior art winches the source of hydraulic fluid and the control valves were normally remote from the winch. For purposes of simplicity of installation, compactness and application to vehicles of varying design upon which a winch may be mounted, it is desirable to provide a winch in which the hydraulic supply and hydraulic controls are an integral part of the winch. This invention pertains to the winch wherein the hydraulic fluid supply and the hydraulic means for actuating the brake and clutch mechanism is entirely contained within the winch body thereby obviating the need for long fluid transmission lines and permitting adaptation for use on various types of vehicles and other equipment.

One of the objects of the present invention is to provide a self-contained winch structure wherein the clutch mechanism, brake mechanism, and controls as well as hydraulic supply for both these mechanisms is entirely contained within the winch structure.

Another object of the present invention is to provide a unique brake structure requiring a minimum actuating force to provide extremely high braking torque.

Yet another object of the present invention is to provide a unique self-compensating hydraulic pump in conjunction with an accumulator which is continuously actuated by the drive train of the winch system whereby assuring a constant supply of fluid at a predetermined pressure. The pump is self-compensating in that when the predetermined pressure is reached the pump will not introduce more fluid from the reservoir into the system until there is a 'drop in pressure below the predetermined pressure.

Still a further object of the present invention is to provide a unique no-leak spool valve for actuating the winch wherein the hydraulic fluid is introduced through the center of the spool valve and exits through one side of such spool valve into any one of a plurality of ports to actuate the clutch, brake, or other mechamsms.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the winch including the integral control and actuating system.

FIG. 2 is an elevational view of the winch of FIG. 1 as seen from the right-hand side of that FIG.

FIG. 3 is an isometric view of the unique brake band assembly and actuating mechanism.

FIG. 4 is an end elevational view with the cover plate partially broken away to show the-details of the hydraulic control system.

' FIG. 5 is a sectional view of the unique control valve.

FIG. 6 is a top view of the valve of FIG. 5.

FIG. 7 is a sectional view of the pump mechanism.

DETAILED DESCRIPTION OF THE DRAWINGS As can be seen in FIGS. 1 and 2, the winch comprises a main winch housing portion 2 which serves to mount the drive shaft 4 and the necessary gearing 6 to ransmit the torque from the drive shaft to a drum mounting shaft 8 which is journal mounted by bearings 10 within the housing 2. At the opposite end of shaft 8 from said gearing 6 is a clutch mechanism 12 and brake mechanism 13. The clutch mechanism transmits the torque from the shaft 8 to the drum 14 upon which the cable 16 is wound. The brake mechanism 13 is for releasing and stopping the drum 14 when it is so desired. For protection and ease of servicing, the main housing 2 of the winch includes removable cover plates 18 and 20 located at opposite ends of the shaft 8. Secured directly to the housing 2 is an adapter housing 22 which will later be described in greater detail. The adapter housing mounts the power take-off shaft 24 which provides the input torque from a prime mover. This power transfer permits any one of the number of optional gearing combinations to transmit the torque to drive shaft 4. It is to be noted in FIG. 1 that the drum 14 includes at its right-hand end, as viewed in this figure, an outwardly extending flange or drive and brake drum 30 the interior of which receives the driving impetus from the clutch 12 and the exterior of which receives the braking force to be supplied by a brake mechanism 13 hereinafter described.

Referring now in particular to FIGS. 2 and 3, the brake mechanism is illustrated in detail. The only attachment of the brake mechanism 13 to the main housing 2 is by means of the pin 50 which passes through an eye connector 52 provided on one end portion of each of a pair of secondary brake bands 54. The opposite end of each of the brake bands 54 includes an anchor tube 56 through which is passed a pin 58. Positioned between the two secondary brake bands 54 is a single primary brake band 62. A bracket 60 is provided on one end and the pin 58 passes through a hole provided in the bracket. Secured to the opposite end of the primary band 62 is a channel shaped lug 64. It is to-be noted that the bracket 60 includes an upstanding portion 66 in addition to the portion wherein the pin receiving hole is formed. Mounted within a bore in the upstanding portion 66 is a brake releasing hydraulic cylinder 68 which is connected by means of shaft 70 to a compression spring 74 mounted within a casing 76. The hydraulic fittings on the cylinder 68 have not been illustrated for clarity. The compression spring and shaft are supported entirely between the portion 66 and lug 64. An adjustment screw 78 is located on the housing and provides a movement limiting stop for the brake band assembly. A spring retainer 75 in the shape of -a stirrup is attached to lug 64 and has a main body portion 76 surrounding spring 74. A pin 72 extends through the rod 70 and the ends of the pin seat in notches 71 provided in the side portions of lug 64.

In operation the force of the spring 74 extends the shft 72 upwardly, as seen in FIG. 2, and this moves the lug 64 and bracket 60, thus tightening the primary band 62. The brake system is designed such that the spring action is only sufflcient to tighten the primary band. The brake bands are placed within the housing in such a manner that the rotation drag when the drum is turning counterclockwise in FIG. 2, will tend to tighten the bands around the drum and the'resultant braking force is achieved many times greater than that applied by the spring pressure. The actual brake force can be determined by standard calculation which of course takes into account the coefficient of friction of the material as well as the amount of wrap. To release the brake bands, the cylinder is activated to extend shaft 70 which does no more than compress the spring and therefore requires only enough hydraulic pressure to act against the spring load. The clockwise rotation, FIG. 2, oi." the drum will cause the bands to unwrap.

As can be seen in FIG. 1, the brake and actuating mechanisms are placed on the one end of the drum 14. When it is desired to partially or totally release the brake, the hydraulic fluid acts upon the piston in cylinder 68 to extend the shaft 70 against the pressure of the spring 74. This moves the lug 64 and primary brake band 62 clockwise thereby reducing the braking friction. The release of tension on the primary brake band will provide complete brake release since the secondary bands are clear of the drum within the limits set by adjustment screw 78. Since the brake bands are placed about the drum in a fashion such that they will tighten when the drum is turning for out-hauling of the cable, rotation of the drum in the other direction will tend to loosen the bands and reduce the drag of the brake bands.

As seen in FIG. 2, the clutch mechanism is located on the interior portion of the drum 30. The clutch mechanism is activated by a hydraulic cylinder supplied with fluid from the control valve, hereinafter, described, and operates through a cam mechanism that is standard and readily available and will not be described in detail.

The control system and actuating mechanism for the winch are located within the adapter housing 22 and main housing 2 referring to FIGS. 1 and 4 in combination, the relative placement of the various parts will be more particularly described. As seen in FIG. 1, the pump 100, to be described in detail hereinafter, is mounted directly below the drive shaft 4 and has an upwardly extended plunger mechanism which is oscillated by engagement with a cam 102 mounted on the drive shaft 4. The drive shaft and cam are continuously rotating when power is provided through shaft 24. These elements can readily be seen in FIG. 4, where it can also be seen that the pump 100 is primarily located within the housing 2 of the winch with only a short portion thereof extending outside the housing and serves as a means to secure the pump in position.

The main control system for the winch is located within the adapter housing 22 which is best seen in FIG. 4 and has the general outline of the forward end of the winch and has at its left forwardmost portion as viewed in FIG. 4, an oil reservoir 106 within which is located a filter 108 interconnected to the supply line 104 for the pump 100. A pressure line 105 from the pump is interconnected to an accumulator 110, which is a precharged unit assuring a constant fluid pressure level. The hydraulic line 112 extends from the accumulator 110 to a valve mechanism 114 which directs and controls the flow of the hydraulic fluid to either the clutch or the brake as desired.

The valve mechanism is mounted partially within the oil reservoir 106 and the specific construction of the valve is illustrated in detail in FIG. 5. The valve has one inlet and two outlets but it is to be understood that this is not intended to be definitive and the number of outlets and resulting number of valve positions is merely a matter of requirement for a specific illustration. The valve comprises two main body portions, one of which is the outlet portion 130 and the other is the inlet portion 132. The two portions are mounted on opposite sides of a mounting plate 133 and are secured together in any appropriate manner such as by means of bolts 134.

The outlet portion of the valve body includes internal fluid passages 136 and 138 and secured at the terminal ends of the passages are appropriate hydraulic fittings for connection to hydraulic transmission lines. The inlet portion of the valve housing 132 includes a circular bore 133 to receive a spool or plunger having an axial bore 151 therein connected to an appropriate hydraulic fitting 154. Intermediate the ends of the spool is a radially extending bore 156 having located herein a spring biased valve 158 and on which is mounted an O-ring 160. Located within the inlet body portion 132 and extending through a hole in the plate 133 is a seal block 162 having bores 137 and 139 therein in communication with the outlet bores 136 and 138. The spool is adapted to move axially within the bore in the body 132 such that the radial bore 156 may be selectively put into communication with bores 137 or 139 in the sealing block 162, or alternatively, when the bore 156 is in the position shown in FIG. 5, there is no flow of fluid to the brake or clutch and the brake is spring engaged and the clutch is disengaged. As previously stated, because of the direction of the wrap of the brake bands, the bands provide a minimum of friction or braking when the cable is in-hauled and no brake releasing pressure is required. The brake releasing cylinder 68 is only actuated when it is desired to out-haul the cable and then the drum 14 is free spooling and the cable may be pulled out manually.

The end of the spool 150 opposite the fitting 154 supports a conventional spring actuated return to center mechanism comprising items 172 to 174. This construction centers the radial bore 156 in a no-flow position as shown in FIG. 5. The valve spool may be moved in either direction by the up of down movement of the lever 146. The lever 146 is secured to a shaft 147 which extends through sleeve 148 mounted in the housing 22. An O-ring 149 is positioned on the shaft 147 to prevent leakage of oil from the reservoir 106. Secured to the other end of the shaft 147 is a connector lever 143 that is in turn secured to the free end of the spool by pin 144.

In this embodiment the spool is raised by moving the lever 146 downward and bore 156 is in communication with bore 137. The clutch is engaged and the operator must necessarily hold the lever in this position so that whenever it is released by accidental means or because of an emergency the spring will center the bore between the outlet bores, the clutch is disengaged and the drive to the drum is terminated. In order to hydraulically release the brake, the operator must raise the lever 146 thereby moving the valve 150 downward so that bore 156 aligns with bore 139. This actuates cylinder 68 and the drum 14 is then freely rotatable.

The pump mechanism which is designed to be continually activated by the input drive to the winch and comprises a generally circular outer casing 200 having an inlet port 202 at one end thereof, said inlet port has a ball check valve 204 to prevent reverse flow. Mounted within the interior of the hollow casing 200 is a compression spring 206 of a predetermined force. One end of the compression spring 206 is bottomed against the inlet end of the casing 200 and the other end of the compression spring abuts a valve seat 208 secured to an axially movable piston 212 having a bore therethrough. The sliding valve seat includes an elongated portion 209 of reduced diameter which is retained in one end of the movable piston 212. The inner end of the piston as at 211 is of larger diameter than the opposite end 213. Radial passages 217 are formed in the piston between the portions of larger and smaller diameter. An

O-ring 214 is positioned on the portion 211 of the piston and another O-ring 216 is positioned on portion 213. The inner end of the piston is axially bored as at 219 and a ball check 210 is positioned in the base of the bore and adapted to be engaged by the end of the valve seat 208. Abutting the other end 213 of piston 212 is a cam follower 218 which is engaged by the cam 102 when the pump is positioned within the winch below the drive 4. Adjacent the portion of the piston 213 is a radial outlet port 220 in communication with a fluid transmission line 224 which leads to the discharge fitting 225 of the pump.

in operation, the cam will oscillate the cam follower 218 alternately compressing and allowing expansion of spring 206. This action forces fluid through inlet port 202 into the chamber surrounding spring 206 the oneway ball check valve 204 closes the port 202 forcing the fluid out through the bore in the valve seat 208 into the radial passages 217 in the piston 212. The movement of the piston in both directions forces fluid outwardly through conduit 224 and fitting 225. The pump is self-compensating in that once a pressure is built up between the differential in the cross-sectional area defined by the portion 211 and 213 terminating in opposed surfaces 215 and 217, the spring 206 will remain compressed and the cam follower will not move outwardly to contact the cam. When the cam follower does not contact the cam, the pump will be at rest until the pressure within the system drops below the spring load allowing the cam follower to be forced against the cam and pumping action will again begin.

It must be readily seen that the combination of the self-compensating pump and the no-leak valve allows the entire control system for the winch to be located within the winch confines except for several sections of the external tubing. The novel construction of the brake mechanism allows ample braking force with a minimal amount of pressure to control the brake release and clutch engage mechanisms.

The embodiments of the invention in which a particular product or privilege is claimed are defined as follows:

l. A self contained fluid pressure controlled winch comprising:

a. a self contained winch housing adapted for containing a winch mechanism and adapted for mounting on various types of vehicles and like equipment;

b. a winch drum rotatably mounted in said housing;

c. a rotatable power input shaft;

d. a gear train connected with said power input shaft;

e. fluid operated clutch means for selectively connecting said gear train with said winch drum;

f. fluid operated brake means for selectively holding said drum against rotational movement with respect to said housing; and

g. fluid control means mounted on said housing for selectively actuating said clutch means and said brake means, said fluid control means including: 1. a fluid reservoir contained entirely within said housing,

2. fluid pump means connected with said gear train and said reservoir and mounted entirely within said housing for converting the rotational energy of said gear train into fluid pressure,

3. accumulator means mounted entirely within said housing for storing fluid pressure for continued operation of the fluid control means should said fluid puinp means fail to operate 4. valve control means for selectively directing fluid pressure from said fluid pump means or said accumulator means to said clutch means and said brake means, said valve control means including a fluid valve contained entirely within said housing, and

5. valve operator means extending through said housing for selectively actuating said fluid valve to direct fluid to said brake means or said clutch means.

2. A self contained fluid pressure controlled winch as defined in claim 1, wherein said fluid operated brake means includes a double wrapped band secured to said winch housing at only one point and a brake actuating mechanism connected with said double wrapped band and supported solely at said one point.

3. A self contained fluid pressure controlled winch as defined in claim 1 wherein said gear train includes a cam and said fluid pump means includes a self compensating pump having a piston actuated by said cam and having biasing means for biasing said piston into engagement with said cam, said piston including fluid differential means for restricting movement of said piston incident to increased fluid pressure to limit operation of said pump means to those periods when the fluid pressure is below a predetermined level, said fluid differential means including a differential annular area on said piston.

' 4. A self contained fluid pressure controlled winch. as defined in claim 3 wherein said piston further includes a valve seat slidingly mounted therein, said valve seat including a through bore and a check valve for restricting fluid flowing in one direction within said bore.

5. A self contained fluid pressure controlled winch as v defined in claim 1 wherein said accumulator means is interconnected between said pump means and said valve means. 7

6. A self contained fluid controlled winch as defined in claim 1 wherein said brake means includes a primary band and a secondary band, one end of said secondary band being secured to said winch housing and the other end of said secondary band being interconnected to one end of said primary band, a hydraulic cylinder interconnected to said primary band and adapted to release the braking action of both brake bands incident to the application of hydraulic fluid to the cylinder.

7. A self contained fluid controlled winch as defined in claim 6 wherein said brake bands are wrapped in a direction which tightens the bands incident to rotation in one direction of said drum when spring pressure is applied to said primary band. 

1. A self contained fluid pressure controlled winch comprising: a. a self contained winch housing adapted for containing a winch mechanism and adapted for mounting on various types of vehicles and like equipment; b. a winch drum rotatably mounted in said housing; c. a rotatable power input shaft; d. a gear train connected with said power input shaft; e. fluid operated clutch means for selectively connecting said gear train with said winch drum; f. fluid operated brake means for selectively holding said drum against rotational movement with respect to said housing; and g. fluid control means mounted on said housing for selectively actuating said clutch means and said brake means, said fluid control means including:
 1. a fluid reservoir contained entirely within said housing,
 2. fluid pump means connected with said gear train and said reservoir and mounted entirely within said housing for converting the rotational energy of said gear train into fluid pressure,
 3. accumulator means mounted entirely within said housing for storing fluid pressure for continued operation of the fluid control means should said fluid pump means fail to operate
 4. valve control means for selectively directing fluid pressure from said fluid pump means or said accumulator means to said clutch means and said brake means, said valve control means including a fluid valve contained entirely within said housing, and
 5. valve operator means extending through said housing for selectively actuating said fluid valve to direct fluid to said brake means or said clutch means.
 2. fluid pump means connected with said gear train and said reservoir and mounted entirely within said housing for converting the rotational energy of said gear train into fluid pressure,
 2. A self contained fluid pressure controlled winch as defined in claim 1, wherein said fluid operated brake means includes a double wrapped band secured to said winch housing at only one point and a brake actuating mechanism connected with said double wrapped band and supported solely at said one point.
 3. accumulator means mounted entirely within said housing for storing fluid pressure for continued operation of the fluid control means should said fluid pump means fail to operate
 3. A self contained fluid pressure controlled winch as defined in claim 1 wherein said gear train includes a cam and said fluid pump means includes a self compensating pump having a piston actuated by said cam and having biasing means for biaSing said piston into engagement with said cam, said piston including fluid differential means for restricting movement of said piston incident to increased fluid pressure to limit operation of said pump means to those periods when the fluid pressure is below a predetermined level, said fluid differential means including a differential annular area on said piston.
 4. A self contained fluid pressure controlled winch as defined in claim 3 wherein said piston further includes a valve seat slidingly mounted therein, said valve seat including a through bore and a check valve for restricting fluid flowing in one direction within said bore.
 4. valve control means for selectively directing fluid pressure from said fluid pump means or said accumulator means to said clutch means and said brake means, said valve control means including a fluid valve contained entirely within said housing, and
 5. valve operator means extending through said housing for selectively actuating said fluid valve to direct fluid to said brake means or said clutch means.
 5. A self contained fluid pressure controlled winch as defined in claim 1 wherein said accumulator means is interconnected between said pump means and said valve means.
 6. A self contained fluid controlled winch as defined in claim 1 wherein said brake means includes a primary band and a secondary band, one end of said secondary band being secured to said winch housing and the other end of said secondary band being interconnected to one end of said primary band, a hydraulic cylinder interconnected to said primary band and adapted to release the braking action of both brake bands incident to the application of hydraulic fluid to the cylinder.
 7. A self contained fluid controlled winch as defined in claim 6 wherein said brake bands are wrapped in a direction which tightens the bands incident to rotation in one direction of said drum when spring pressure is applied to said primary band. 